The answer is
C. A single replacement reaction (acid reactions)
An example would be the reaction between simple metal Potassium (K) and Water (H2O), resulting in a much solid compound called Potassium Hydroxide (KOH) and hydrogen gas is set free.
K+H2O --> KOH
In a reduction-oxidation or better known as REDOX reaction, the substance that reduces the oxidation state is known as the substance that is REDUCED. It serves as the oxidizing agent. Thus, Au3+ in this number is considered as the oxidizing agent.
Answer:
Repulsive forces exist only when atoms are very close to each other. (3/14) "They [the atoms] will approach until both nuclei will simply shove each other because both of them are positive." The balance between the attraction and repulsion forces determines how close the atoms can get. The relationships between the magnitude and direction of repulsive and attractive forces. A stable state of a bond is when attractive forces balance repulsion forces. “A stable state between two atoms is when they attract each other with a force that equals the force that they repel each other.”
The maximum number of covalent bonds formed by a single carbon atom is 4